istio: ingress with grpc and http - istio

Question

I have a service listening on two ports; one is http, the other is grpc.
I would like to set up an ingress that can route to both these port, with the same host.
The load balancer would redirect to the http port if http/1.1 is used, and to the grpc port if h2 is used.
Is there a way to do that with istio ?
I made a hello world demonstrating what I am trying to achieve :
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: hello-world
namespace: dev
spec:
replicas: 1
template:
metadata:
annotations:
alpha.istio.io/sidecar: injected
pod.beta.kubernetes.io/init-containers: '[{"args":["-p","15001","-u","1337","-i","172.20.0.0/16"],"image":"docker.io/istio/init:0.1","imagePullPolicy":"Always","name":"init","securityContext":{"capabilities":{"add":["NET_ADMIN"]}}}]'
labels:
app: hello-world
spec:
containers:
- name: grpc-server
image: aguilbau/hello-world-grpc:latest
ports:
- name: grpc
containerPort: 50051
- name: http-server
image: nginx:1.7.9
ports:
- name: http
containerPort: 80
- name: istio-proxy
args:
- proxy
- sidecar
- -v
- "2"
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
- name: POD_IP
valueFrom:
fieldRef:
fieldPath: status.podIP
image: docker.io/istio/proxy:0.1
imagePullPolicy: Always
resources: {}
securityContext:
runAsUser: 1337
---
apiVersion: v1
kind: Service
metadata:
name: hello-world
namespace: dev
spec:
ports:
- name: grpc
port: 50051
- name: http
port: 80
selector:
app: hello-world
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: hello-world-http
namespace: dev
annotations:
kubernetes.io/ingress.class: "istio"
spec:
rules:
- host: hello-world
http:
paths:
- backend:
serviceName: hello-world
servicePort: 80
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: hello-world-grpc
namespace: dev
annotations:
kubernetes.io/ingress.class: "istio"
spec:
rules:
- host: hello-world
http:
paths:
- backend:
serviceName: hello-world
servicePort: 50051
---

Answer 1

I'm a bit late to the party, but for those of you stumbling on this post, I think you can do this with very little difficulty. I'm going to assume you have istio installed on a kubernetes cluster and are happy using the default istio-ingressgateway:
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: hello-world
namespace: dev
spec:
replicas: 1
template:
metadata:
annotations:
alpha.istio.io/sidecar: injected
pod.beta.kubernetes.io/init-containers: '[{"args":["-p","15001","-u","1337","-i","172.20.0.0/16"],"image":"docker.io/istio/init:0.1","imagePullPolicy":"Always","name":"init","securityContext":{"capabilities":{"add":["NET_ADMIN"]}}}]'
labels:
app: hello-world
spec:
containers:
- name: grpc-server
image: aguilbau/hello-world-grpc:latest
ports:
- name: grpc
containerPort: 50051
- name: http-server
image: nginx:1.7.9
ports:
- name: http
containerPort: 80
- name: istio-proxy
args:
- proxy
- sidecar
- -v
- "2"
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
- name: POD_IP
valueFrom:
fieldRef:
fieldPath: status.podIP
image: docker.io/istio/proxy:0.1
imagePullPolicy: Always
resources: {}
securityContext:
runAsUser: 1337
---
apiVersion: v1
kind: Service
metadata:
name: hello-world
namespace: dev
spec:
ports:
- name: grpc
port: 50051
- name: http
port: 80
selector:
app: hello-world
---
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
name: hello-world-istio-gate
namespace: dev
spec:
selector:
istio: ingressgateway
servers:
- port:
number: 80
name: http
protocol: HTTP
hosts:
- "*"
- port:
number: 50051
name: grpc
protocol: GRPC
hosts:
- "*"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: hello-world-istio-vsvc
namespace: dev
spec:
hosts:
- "*"
gateways:
- hello-world-istio-gate
http:
- match:
- port: 80
route:
- destination:
host: hello-world
port:
number: 80
tcp:
- match:
- port: 50051
route:
- destination:
host: hello-world
port:
number: 50051
The above configuration omits your two Ingresses, and instead includes:
Your deployment
Your service
An istio gateway
An istio virtualservice
There is an important extra piece not shown, and I alluded to it earlier when talking about using the default ingressgateway. The following line found in "hello-world-istio-gateway" gives a clue:
istio: ingressgateway
This refers to a pod in the 'istio-system' namespace that is usually installed by default called 'istio-ingressgateway' - and this pod is exposed by a service also called 'istio-ingressgateway.' You will need to open up ports on the 'istio-ingressgateway' service.
As an example, I edited my (default) ingressgateway and added a port opening for HTTP and GRPC. The result is the following (edited for length) yaml code:
dampersand#kubetest1:~/k8s$ kubectl get service istio-ingressgateway -n istio-system -o yaml
apiVersion: v1
kind: Service
metadata:
<omitted for length>
labels:
app: istio-ingressgateway
chart: gateways-1.0.3
heritage: Tiller
istio: ingressgateway
release: istio
name: istio-ingressgateway
namespace: istio-system
<omitted for length>
ports:
- name: http2
nodePort: 31380
port: 80
protocol: TCP
targetPort: 80
<omitted for length>
- name: grpc
nodePort: 30000
port: 50051
protocol: TCP
targetPort: 50051
selector:
app: istio-ingressgateway
istio: ingressgateway
type: NodePort
The easiest way to make the above change (for testing purposes) is to use:
kubectl edit svc -n istio-system istio-ingressgateway
For production purposes, it's probably better to edit your helm chart or your istio.yaml file or whatever you initially used to set up the ingressgateway.
As a quick aside, note that my test cluster has istio-ingressgateway set up as a NodePort, so what the above yaml file says is that my cluster is port forwarding 31380 -> 80 and 30000 -> 50051. You may (probably) have istio-ingressgateway set up as a LoadBalancer, which will be different... so plan accordingly.
Finally, the following blog post is some REALLY excellent background reading for the tools I've outlined in this post! https://blog.jayway.com/2018/10/22/understanding-istio-ingress-gateway-in-kubernetes/

Answer 2

You may be able to do something like that if you move the grpc-server and http-server containers into different pods with unique labels (i.e., different versions of the service, so to speak) and then using Istio route rules, behind the Ingress, split the traffic. A rule with a match for header Upgrade: h2 could send traffic to the grpc version and a default rule would send the rest of the traffic to http one.